Infra Red Scanning
Thermography, or thermal imaging
as it is sometimes called, is a condition monitoring technique that measures
the radiant heat pattern which is emitted from a body, such as machinery,
electrical boxes or plant equipment, to determine regions or points of
increased, or reduced, heat emission, which can indicate the presence of a
fault in the mechanism's body.
Infra-red, as it is commonly
called, is an extremely versatile and powerful condition non-contact thermal
monitoring tool. Heat levels can be recorded, quantified, and diagnosed as
either normal or abnormal, based on specific parameters established by
equipment manufacturers and industry standards. This process requires no contact
with, or the shutdown of, equipment thus allowing detection of any problems
at the earliest stages. Infra-red scanning has consistently proven itself by
reliably identifying trouble areas, avoiding costly, or even catastrophic,
equipment failures.
Infra-Red scanning works by
revealing invisible thermal patterns that correspond directly to reliability
problems. Normal current flow through a loose or corroded connection, or by
an otherwise failing electrical component results in abnormal, elevated temperatures.
Before it is hot enough to cause an outage or other problems, the abnormal
heating patterns are quickly and easily detected by infra-red scanning.
A FLIR
Systems – Thermacam PM595
infrared camera is used to capture a real time image, which is stored on a
removable PCMCIA card. A 24 degree integral lens is used on the Infra Red
Camera to provide resolution from 12” to infinity. A single point temperature
measurement is used on peak hold, recording the maximum and minimum
temperatures (usually phase to phase). The image stored on the Camcorder is
later processed via computer and various graphics programs to produce
individual thermograms for each reported HOT-SPOT. IRWIN 5.3 is used
to generate the report, which includes a SUMMARY of
INSPECTION as the last
page. The report
also contains the field notes, which further detail the hot spot location of
each thermogram. A spreadsheet of items inspected, location, component,
temperature, and repairs can also be provided for trending.
